1. Field of the Invention
The field of the present invention is an intake system of a multi-cylinder internal combustion engine which may contribute to enhancing the output performance of the engine by improving the charging efficiency of intake air to respective cylinders.
2. Description of the Prior Art
It has conventionally been known, for the purpose of improving the charging efficiency of intake air to respective cylinders, to connect a relatively long, first intake duct and a relatively short, second intake duct in parallel fashion to each of the cylinders and to feed the intake air to the cylinders through the first duct in a low speed operational range of the engine and through the second duct in a high speed operational range of the engine thereby raising the charging efficiency with use of an inertia effect over a wide range of engine operation (see Japanese Patent Application Laid-open No. 61-116022, for example).
A conventional intake system of the mentioned type suffers such a problem, however, that the construction of intake ducts is complicated and thereby makes the system large-sized.